Container Basics On Linux (Namespaces/Cgroups)

See through the cgroup fog before your host falls over

🧩 The Challenge

Dealing with a container that is hitting memory limits is a nightmare when you have no idea which cgroup it belongs to. You end up grepping through a mountain of nested directories in sysfs while the server is actively gasping for air.

💡 The Fix

Use systemd-cgtop to get a live, interactive view of your resource consumption by slice. It saves you from digging through raw kernel files when a process is clearly eating your lunch.

systemd-cgtop

⚙️ Why It Works

This tool taps into the kernel’s cgroup accounting data and refreshes it in real-time, essentially giving you a top-like interface for your containers. You stop wasting time hunting for PID files and see exactly who is hitting those memory ceilings immediately.

🚀 Pro-Tip: Press ‘k’ while in the tool to instantly send a SIGTERM to the top process if you need to clear memory in a hurry.

Linux Tips & Tricks | © ngelinux.com | 10/7/2026